Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China.
Molecules. 2022 Apr 21;27(9):2682. doi: 10.3390/molecules27092682.
Hydroxypropyltrimethyl ammonium chloride chitosan (HACC) is one of the most important water-soluble chitosan derivatives; its derivatives have gained growing attention due to their potential biomedical applications. Here, hydroxypropyltrimethyl ammonium chitosan derivatives bearing thioctate (HACTs), with different degrees of substitution of thioctate, were prepared using HACC and α-lipoic acid as the reaction precursors, using an ion exchange method. The structural characteristics of the synthesized derivatives were confirmed by FTIR, H NMR, and C NMR spectroscopy. In addition, their antioxidant behaviors were also investigated in vitro by the assays of reducing power, and scavenging activities against hydroxyl radicals and DPPH radicals. The antioxidant assay indicated that HACTs displayed strong antioxidant activity compared with HACC, especially in terms of reducing power. Besides, the antioxidant activities of the prepared products were further enhanced with the increase in the test concentration and the degrees of substitution of thioctate. At the maximum test concentration of 1.60 mg/mL, the absorbance value at 700 nm of HACTs, under the test conditions, was 4.346 ± 0.296, while the absorbance value of HACC was 0.041 ± 0.007. The aforementioned results support the use of HACTs as antioxidant biomaterials in food and the biomedical field.
羟丙基三甲基氯化铵壳聚糖（HACC）是最重要的水溶性壳聚糖衍生物之一；由于其在生物医学方面的潜在应用，其衍生物越来越受到关注。在这里，使用 HACC 和α-硫辛酸作为反应前体，通过离子交换法制备了具有不同取代度的巯基乙酸酯（HACTs）的羟丙基三甲基铵壳聚糖衍生物。通过傅里叶变换红外光谱（FTIR）、核磁共振氢谱（1H NMR）和核磁共振碳谱（13C NMR）对合成衍生物的结构特征进行了确认。此外，还通过还原力、羟基自由基和 DPPH 自由基清除活性测定法对其体外抗氧化行为进行了研究。抗氧化测定表明，与 HACC 相比，HACTs 具有很强的抗氧化活性，尤其是在还原力方面。此外，随着测试浓度和巯基乙酸酯取代度的增加，制备产物的抗氧化活性进一步增强。在 1.60mg/mL 的最大测试浓度下，在测试条件下，HACTs 的 700nm 处的吸光度值为 4.346±0.296，而 HACC 的吸光度值为 0.041±0.007。上述结果支持将 HACTs 用作食品和生物医学领域的抗氧化生物材料。
